Borehole inclination transmitter



May 21, 1940. D. E. McKEE. 2,201,909

BOREHOLE INCLINATION TRANSMITTER Filed May 19, 1936 3 Sheets-Sheet 1 E E-Z- ATTORNEY May 21, 1940.

D. E. M KEE BOREHOLE INCLINATION TRANSMITTER Filed May 19. 1936 3 Sheets-Sheet 2 u I H 5 y fi Z, w A 5 z 5 1 all! m L M J} 2 Z M 6 I J 1 J3 1 1 7/! 4/ Q L m, 9

ATTORNEY D. E. McKEE May 21, 1940.

BOREHOLE INCLINATION TRANSMITTER Filed May 19, 1956 3 Sheets-Sheet 5 REID.

ATTORNEY Patented May 21, 1940 BOREHOLE INCLINATION TRANSMITTER Donald E. McKee, Fort Worth, Tex., assignmof one-half to H. F. Spreen, Fort Worth, Llex.

Application May 19, 1936, Serial No. 80,516

3 Claims.

This invention relates to oil field engineering and it has particular reference to apparatus for accurately directing drilling operations to insure a true vertical course of the bit and its principal object resides in the provision of such a method whereby the minimum of deviation from the vertical can be quickly and easily determined without unduly interrupting drilling operations and thus enabling the operator to make frequent observations and correct any deflections which may occur before they reach major proportions.

Another object of the invention resides in the provision of a device for determining, by audible signals, whether or not the tools are following a true vertical course or the lateral inclination of the bit from a vertical course and the degree of inclination at regular intervals, as the tools progress downwardly, and prevent the usual expensive loss of time and effort in acquiring such information by the use of ordinary clinographs, and the like.

A still further object of the invention lies in the provision of apparatus for orienting oil wells by intentionally deflecting the bit in order to reach a formation remotely situated with respect to the customary vertical course and which can only be negotiated by directing the tools at the required angle accomplished by proper triangulation.

Broadly, the invention seeks to comprehend the provision of a device for audibly determining, at desired intervals, the degree of lateral disposition of the bit and its directional inclinations without pulling the tools or otherwise suspending drillirifi perations more than a few minutes.

While the foregoing objects are paramount,

other and lesser objects will become manifest as the description proceeds, taken in connection with the appended drawings herein.

Figure 1 is a partial vertical cross-sectional view of the upper portion of the apparatus used in effecting the results of the said method illustrating the driving mechanism and the detonating or sound producing elements in the topmost end thereof.

.Figure 2 is a vertical cross-sectional view of the middle section of the structure used in carrying out the herein described method showing the mercury switch and the pendulum contact.

Figure 3 is a partial cross-sectional view of the lowermost portion or battery casing.

Figure 6 is a lateral cross-sectional view of the detonator contact taken on lines 6-6 of the Figure 1.

Figure 7 is a lateral cross-sectional illustration of the gear nest taken on lines l! of Figure 1. 5

Figure 8 is a lateral cross-sectional view of the spiral-like passage for the quantity of mercury utilized to energize the assembly taken on lines 8-8 of Figure 2.

Figure 9 is a diagrammatic illustration of the 10 wiring circuit 0f the apparatus.

Figure 10 is a plan view of the upper face of the concentrically arranged contact rings engaged by Figure 4 is a diagrammatic illustration of a the lowermost end of the pendulum taken on lines l0l0 of Figure 2.

Figure 11 is an inverted plan view of the pendulum taken on lines H-ll of Figure 2.

Figure 12 is a view of the cushioning device for the apparatus for supporting the same in the drill stem.

It is highly desirable to project a well downwardly as accurately as possible on a vertical plane so that the various formation above that which is desired to be reached may be negotiated in the most direct course and in order that this may be accomplished it is necessary to determine, at all times, the downward vertical progress of the tools which, under ordinary conditions will vary to some extent at least, from a vertical due to the presence of hard formation and faults which serve to deflect the bit from a straight course and due to the fact that a rotating body when progressed tends to follow a spiral course. Other conditions will necessitate the orientation of the bit to direct the same from a vertical in order to reach a stratum or formation located remotely from the source of the operations, that is, to deflect the bit so as to accomplish a complete well wherein the source of production is found to be situated in an area inaccessible by strictly perpendicular operations.

The herein described invention will enable the operator to adhere consistently to the most direct course in the drilling operations whether it be a strict adherence to the vertical or an angular deviation therefrom, determining the degrees of deviation at predetermined intervals with the minimum of effort and cessation of operations.

The apparatus is especially designed to cooperate' with the drilling tools and which consist primarily of a cylindrical casing l adapted to repose within a drill stem 2, as illustrated in Figures 1, 2 and 3. The casing l receives a housing 3 which contains the assembly of working parts constituting the apparatus utilized in carrying cap 4 is situated a solenoid coil 6 housed within the inverted truncated cone-like structure I which projects upwardly through an annular opening A in a ring I which is welded to the casing 3. The solenoid 6, when energized, oper-' ates a plunger 8 at the upper end of which is an integral ball shaped striking element 3 which is brought in contact with the lowermost surface a of the conical member 5 situated in the cap 4 by the solenoid 6 in sharp, quickly executed raps producing a detonation whose sound wave is propagated lnto the column in drilling fluid and which, under normal conditions, such as moderate depth of the hole and light weight drilling fluids, gives a distinctly audible sound signal at the earths surface.

Under abnormal conditions, such as extreme depth of the hole or dense and heavy drilling fluids, or other conditions which tend to dampen out the sound signal and render it inaudible to the ear, a simple battery microphone with headphone, is attached at some convenient point on the drilling fluid circulating system to further enable the operator to hear the signal distinctly.

The plunger 8 in the solenoid 6 is-provided, at its lowermost end, with a tapered or inverted conical contact member H! which is attached to the plunger 8 through the medium of a stem ll projecting upwardly into a recess i2 containing a spring [3 which normally retains the contact member In in its lowermost position. The assembly is retainedwithin the recess [2 by means of a pin l4 extending laterally through slots in the lower end of the plunger 8 and through the stem ii of the member ID.

The solenoid 6, as well as other operating elements incorporated into the apparatus, is energized by a battery of dry cells which is illustrated in Figures 3 and 4. These elements will be described in detail as the description proceeds.

A complete wiring circuit is necessary in the proper function of all the parts of the apparatus coordinating to produce the desired results and such circuit will be described in the logical sequence as it relates to the various moving parts ,and the proper function of the apparatus.

The contact member 18 operates on a vertical plane and, while in its lowermost position, its tapered sides repose within an aperture 17 formed between two opposingly arranged semi-circular metal plates l6, as shown in Figure 6, whose in-- her wallsare beveled to conform to the tapered surface of the member I!) and thus a connection is completed between the contact member in and the plates l6 which are retained in position by bolts or screws H, as illustrated in Figures 1 and 6, to a supporting plate l8 of a non-conductive material, held in position by bolts or screws l9 threaded into bosses 20.

The plates iii are separated from the plate H! by a ring c of non-conductive material and the bosses 20 are integral with a circular insulating plate (1. The entire assembly just described is housed within a circular chamber 2| in the upper portion of collar of' non-conductive-material 22 positioned within the housing 3. One side of the winding of the solenoid 6 is grounded to the casing 3 through the structure 11' A wire 23 extends from the opposite side of the winding of the solenoid 6 to one of the screws l'l, through one of the plates l6 while another wire 24 is connected to the opposite screw I1 and extends through a passage 25 downwardly to the source as will be presently shown.

An annular recess 26 is provided in the lower portion of the collar 22 of non-conductive material which receives the upper end of a cylindrical casing 21 whose lowermost end projects into a ring 28 and rests upon an annular shoulder 29 therein. An electric motor 30 is mounted within the casing 21 and is provided with a vertically arranged shaft 3! which is mounted in bearings 32 and 33 situated within the-upper and lower ends of the casing 21. as illustrated in Figure l. A

semi-flexible coupling 34 of non-conductive material is attached to the lowermost end of the shaft 3! which connects the latter with the uppermost end of a shaft 35 which extends down-- wardly through a gear box 36 which is positioned within a collar 36' and in which is situated a series of reduction gears and pinions which serve to increase the torque and to control the speed of the shaft 35 in the operation of the other mechanism housed within the main casing 3 of the apparatus.

The gear assembly consists of a pinion 31 which is rigidly secured to the shaft 35 just inside the box 36 as illustrated in Figure 1, and is centrally located therein so as to mesh on each side with gears 38 and 39 which are freely mounted upon pins or stationary shafts 40 which extend vertically through the gear box 36 on each side of the pinion 31 and are parallel with the shaft 35.

Integral with each of the gears 38 and 39 are pinions 4i and 42 whose teeth engage those of an idler gear 43 freely mounted upon the shaft 35. The pinion 44 integral with the gear 43 meshes with another pair of larger gears 45 and 46 also freely, mounted upon-the shafts 46, each having integral pinions 41 and 48 which mesh with a larger gear 49 having a downwardly extending hollow integral shaft 58 which revolves around the shaft 35 and within a bearing or boss 5| integral with and extending downwardly from the bottom of 'the gear box 36.

The integral hollow shaft 50 is slotted at e and receives the upper end of another vertical shaft 52 having a pin 53 extending therethrough whose projecting end extends into the slot, e so that the shaft 52 will rotate with the shaft 50 when the latter is driven by the motor 30 through the shaft 3| and the'gear assembly in the gear box 36.

The herein described method contemplates the provision as previously stated, of a method for determining the vertical course or the lateral deviation from a vertical course assumed by the under portion a of the member 5 in the dome 4 of the housing 3. The sounds thus produced are carried by the liquid in the drill system to the earth's surface.

Provision is made to afiord an arrangement whereby the operator can be. definitely apprized of the extent of deviation from a vertical by providing means of causing the plunger 8 to operate at desired intervals and tap the member 5 a number of times and which number may be equal to the number of degrees of deviation plus one,

a single detonation signifying a true vertical position of the apparatus. For example, if the deviation amounts to one degree the plunger will operate to tap the member 5 two times at predetermined intervals. If the number of degrees is two the member 5 will be tapped three times at predetermined intervals and so on.

Thus, the shaft 52 extends downwardly through a plate of non-conductive material 54 and a bearing 55 as illustrated in Figure 1, while its lowermost end is received by a bearing 56 disposed within a plate 51 ofnon-conductive material which is connected to the plate 54 by vertical standards 56 and 59 of non-conductive material. The shaft 52 is surrounded by a metal sleeve 6'9'which is adapted to rotate therewith and carrying a receiving disk 6| which is arranged above, a series of superimposed contact segments, each of which are fixed to and rotate with the sleeves 59, and which are illustrated diagrammatically in Figure 9. The lowermost segment 62 of the series being an intermittent ground connection whose function will presently become manifest.

As illustrated in Figure 9, the receiving disk 5! is provided with a smooth continuous and unbroken outer periphery while the ground contacts projecting axially therefromand which are 7 contacted by spring tensioned arms 64 to which the wires 1. g, h. i, a and k are connected from the source. 7

Figure 9 shows the segment or contact disk 65 immediately beneath the receiving disk 5| as having only one contact finger 63 while the disks 65, 51, 66 and 59 are shown as having two, three, four and five contact fingers 63 respectively. As the shaft 52 is rotated, therefore, the tensioned contact arms 54 willengage the fingers 63 of the segments intermediate the receiving disk 6| and the ground segment 52 and intermittently energize the solenoid 6 through the receiving disk 6I and the line 24. p

The arrangement of the disks 65 to 59, illustrated diagrammatically in Figure 9, on the shaft 52 and the sleeve 69, is such that the contact sequence of the fingers 63 with the spring tensioned arms 64 thereof is such that the first of the series of fingers 63 on each of the disks 65 to 69 will engage the tensioned arms 64 thereof simultaneously when the disks are rotated anticlockwise. It is pointed out that there are provided five of these elements, each having, re-.

spectively, from one to five contact fingers 69. Thus, when the single contact finger 63 of the disk 65 is in contact with its tensioned arm 54, the first finger 63 of each of the other disks 66 to 69 are also in engagement with their respective arms 64; When this contact is broken as the disks rotate, the second contact finger 63 .of each of the disks 66 to 59 are in simultaneous engagement with their respective arms 64 until their rotation causes the breaking of such contact and the third contact fingers 63 of the remaining three disks 6! to 69 are in simultaneous engagement with their respective arms 64 and whereupon, as the disks rotate. the fourth fingers 69 of the disks 69 and 69 come into simultaneous contact with their arms 54 and, finally, the last contact is made through the fifth contact finger 53 on the last disk 59.

The ground segment 62 is positlonedand timed on the sleeve 65 in such a manner as to close its circuit before the first contacts 53 of the disks 65 to 59 close with the spring tensioned arms 64 and to hold this circuit closed until after the fifth contact 63 of the disks 69 has closed with the spring tensioned arm 64 and then opened, as illustrated diagrammatically in Figure 9. It will 'be noted from referenceto Figure 9, that the segment 62 is fully insulated from the shaft 52, the sleeve 59 and the disks 6|, 55 to 59 by the insulator m..

The assembly is designed to be a self-contained water-tight appliance which reposes within the drill stem during all normal drilling operations and to be removed only at such times as battery replenishment is necessary, or at such times as it is desirable to ream the hole, take cores, and the like.

To be effective the assembly is placed within the drill stem 2 in as close proximity to the drill bit as is practical. Therefore, the assembly is designed to fit within a special section of hydraulic pipe which is fitted with tool joints and which connects to the drill collar at the extreme bottom of the drill stem. Ample space for the circulation of drilling fiuid is provided for by the circular passage 2' between the drill stem. 2 and the casing l, shown in Figures 1, 2 and 3.

With the assembly in proper position within. the drill stem, any rotary motion, clockwise or anti-clockwise, of the drill stem 2, is transmitted to the assembly by the apparatus shown in Figure 12, therefore, the assembly rotates with the drill stem as the latter is operated within the well in its different operations in drilling. This rotary motion is made use of for controlling the appliance and to bring the same into operative orinoperative positions.

The rotary clockwise rotation of the drill stem 2 as in drilling, tends to cause the appliance to assume the silent or off position. Therefore, to cause the appliance to function to propagate a signal the drill stem is brought to rest from clockwise rotation, then rotated clockwlse one or two revolutions to effect the closing of the circuit which energizes the motor 39 and the solenoid 6.

The circuit, as illustrated in diagrammatic detail in Figure 9. is energized by a quantity of mercury which is caused to come to rest between two non-amalgamating metal contacts to com-q plete the circuit and which is dislodged by the rotation of the drill stem 2 as will be presently shown. 7 4

The main switch, therefore, consists of a substantially solid cylindrical mass of non-conductive material which is comprised of an upper section 12 and a lower section '13, each of which is provided with a spiral like groove 14, as is shown in Figure 8, which communicates at one end with a concave recess 15, situated near the outer edge of the section, and terminates in a central recess 15. Thus, when the two sections are assembled as shown in Figure 2, a spirallike passage 11 is provided within the member ll and a chamber 78 is formed in the center of which is provided by the recess I6 in each ofthe members 12 and 13, as shown in Figure 8. 4

The lower section 13 of the assembly H is surrounded by a ball race 19 of metal to accommodate ball bearings 89 which operate within a race 8| also of metal and which surrounds the lowermost end of the member I8 and rests upon a metal ring 82 which reposes within an annular recess 88 in the upper end of a collar 84 ofa non-conductive material. Another collar 85 of an insulating material is situated immediately above the collar 84 and provides an insulated casing for'the switch assembly II which is covered by a circular plate 88 secured to the collar 85 by screws 81. The collar 85 is fixed to the housing 8 by screws 85', or the like;

Extending downwardly through the upper section I2 of the assembly II is a stem 88, which' is secured to the member I2 by lock-nuts 88, terminating within the recess I8 in a contact' point 98 which is of a substantially inverted cone-shaped structure having a concave surface. Immediately beneath-the contact 88 and spaced apart therefrom is provided another contact 8| which extends upwardly through the section I8 function will be presently described.

In the lower portion of the collar 84 another annular recess 84 is provided to receive a metal face is concave and which is adapted to serve as a race for balls 91 whose inner face 88 is pendulum I88 is provided a hollow nipple I88 the head 89 of the pendulum I88 which is capasecured to and surrounds a head 88 of a pendulum I 88. The concave face of the ring 88 affords a liberal surface under which the bearings 81 may freely operate therearound or laterally, with respect to a common circular course, thus providing a universal action of the bearing allowing the head 88 of the pendulum I 88 to rotate as well as to swing from side to side. The ring 88 is separated from the' retaining collar IN by insulating material I82. The collar I8I supports the assembly, as illustrated in Figure 2, and which is welded, or otherwise secured within the casing 8.

Projecting upwardly from the head 88 ofthe in which is situated a plunger I84 supporting a ball I85 and which normally urges the latter, by reason of a spring I88, against the concave undersurface' 88 of the boss 82. It will be noted that by reason of the fact that the face 88 of the boss 82 is concave, the ball I85 may closely contact the surface at any point of its area since it is capable of being moved under thesurface in any direction by reason of its association with ble of circular or lateral movement in any direction due to the manner in which it is suspended by the bearing assembly 88, 81, and 88.

As stated, a suitable quantity of mercury is deposited within the recess I5, shown in Figure 8, when the sections I2 and I8 of the switch II are assembled and it is free to travel in the spiral-like passage 11 which graduates downwardly from the recess I5 to the central chem ber I8 where it provides an' electrical "connection between the contacts 88 and 8i, thus completing a circuit through the retaining plate I8, the ball race I8, the ball bearing 88, the outer race 8|, the metal .rings 82 and through the WI attached thereto motor windings. The negative side of the motor winding is grounded to the casing 8, as shown in Figure 9.

mm the rotation of the motor 88 the contact segment 82, shown in Figure 1 and the diagrammatic Figure 9, closes the contact with the two lower spring-tensioned contacts 84 thereby energizing the pendulum circuit. The electrical circuit is then completed through the boss 82 and the ball I85 contacting the concave face 88 through the plunger I84 and the spring I88 which is in direct contact with the-metallic conduit 88' extending downward through'the center of the pendulum I88 to the bob 'III. This circuit isfurther carried through the metallic conduit 88' to the positive side of the windings of the solenoid H8, and is also connected to the solenoid plunger II2 through the spring I I8 as shown in Figures 2 and the diagrammatic illustration in Figure 9. I

A negative connection for the solenoid H8 is also provided in an insulated wire connection I88 which is secured at one end to the negative side of the solenoid winding and extends upwardly through the metallic conduit 88' of the pendulum I88 to the retaining plate I88,-as is shown in Figure 2. The circuit thus provided is completed through the race 98, the ball bearing 81, the

outer race 88, the metallic ring 85 and the insulated wire connection II4 to the spring tensioned contact '84, through the contact segment H5 (82) to the opposite spring tensioned contact 84,'and thence to the casing 8, as is shown in Figure 2 and in the diagrammatic illustration in Figure 9.

It will be noted by reference to Figure 9 that this circuit is open and closed by the contact segment I I5 (82) rotating in proper sequence with the disks 85 to 88, and that this circuit is closed over a suflicient period of time to allow any and all of the contact points 88 on the disks 85 to 89, to make complete contact with the spring tensioned contacts 84 and to fully complete their respective circuits.

It is also pointed out that through'this intermittent ,energizing of the solenoid H8 in Figure 2, that the plunger II2 and a contact point III are periodically released from contact position, thus the pendulum I88 in the bob III will be freed periodically to readjust their position in any event thatthe first contact point selected is not in atrue vertical line. It is further pointed out that this intermittent flow of electrical current tends to conserve battery energy.

As shown in Figure 2 and the diagrammatic illustration in Figure 9 the solenoid H8 is provided with a plunger II2, which, when the solenoid H8 is not energized, is normally retained in its uppermost position by the coil spring II8. This plunger I I2 preferably comprises a thin brass tube closed to a sharp conical shape at its lowermost end I", the upper half being filled with a soft iron core secured within the latter, which gives positive downward pressure to the plunger II2 against the action of the coil spring 8 when the solenoid H8 is energized and a. magnetic field is set up within and surrounding the windings of the solenoid II8. This downward movement of the plunger. II2 causes the contact point III to engage and impart positive battery potential to some selected metallic point on the selector plate III, as shown in Figure 2.

The contact 88 extending into the chamber I8 is connected directly to a line II8 which extends to the source, as shown in Figure 8 and in the diagrammatic Figure 9, which will be presently described. An inverted plan view of the pendulum I00, taken on lines II-H of Figure 2, as shown in Figure 11.

The position of the pendulum I00, that is, the suspended position of the bob Iii thereof, controls the audible signalling apparatus through the medium of the member 5 in the dome 4 of the casing 3 when contacted by the striking element 9 actuated by the solenoid 5. The bob III of the pendulum I00 is secured to the lowermost end of the latter in such a manner as to enable its vertical adjustment thereon so that the lowerary contacts in relatively close proximity thereto so as to insure the proper function of the contact when the contact point In comes to rest above any one of the stationary contact rings.

The selector plate ill just referred to is positioned immediately below the bob III of the pendulum I00, as shown in Figure 2, and consists of a ring N8 of non-conducting material where in is concentrically arranged a series of metal rings, H9, I29, I2I, and I22 which are separated by annular rings of insulating material I23, as shown in Figures 2 and 10.

In the center of the assembly is a single round core I23 which is also of metal. The assembly is secured within the casing 3 by means of an annular collar I26 which is welded or otherwise secured to the casing 3 and is provided with a recess in its lowermost side to accommodate the assembly, as illustrated in Figure 2 The upper .face of the assembly is concave and each of the insulating rings I23 extend slightly above the metal contact rings H9 to I22, as well as the core I 23', to form relatively sharp annular ribs 1 which act to guide the contact engagement on the selected contact ring or core when the solenoid I I!) is energized and the plunger H2 is urged downwardly bringing the contact point II I into engagement therewith. Another important feature of the sharp upwardly projecting ribs Z is in the angular faces thereof as shown in Figure 2, which function to impart a sliding or lateral movement to the contact point I H of the plunger II 2 as it is forced into contact position with the selected point on one of the contact rings II9, E20, MI, and I22 or the metal core I23. This sliding or lateral movement of the contact point H1 insures a clean and positive electrical contact between the latter and the selected con tact.

When a signal is desired. it is .very important that the signal propagated by the appliance will signify with moderate accuracy the true position of the pendulum I00 and the bob I II with r respect to a vertical, in relation to the casing I and the drill stem 2, thereby indicating with reasonable accuracy the actual position of the drill stem in relation to a true perpendicular or vertical position.

The selector plate II I shown in Figures 2 and 10 is comprized of the metal core I23 and the concentrically arranged metal contact rings II9, I20, I2I, and I22, and spaced apart by the insulating rings I23 in such a form and position in its relation to the pendulum I00, the bob HI and the contact point In as shown in Figure 2, that when the contact point I I1 engages the core I23 as signal of one detonation is propagated at regular intervals indicating an approximate perpendicular position for the drill stem. If the contact point I" should engage a point on a contact ring I 22, a signal of two detonations is propagated, indicating an inclination of the drill stem of approximately one degree from perpendicular.

In other words, the selector plate H7 is so designed, formed and positioned'in its relationship with the pendulum III!) the bob III and the contact point II! that should the drill stem 2 incline from a perpendicular position two degrees the contact point In. will be suspended directly over some point on the contact ring I2I and should the drill stem incline .from a perpendicular position three degrees the contact point II'I will be suspended directly over some point on the contact ring I20 and so on. Therefore it will be seen that the audible signal generated by an appliance of this particular design, is indicated in whole degrees and not in fractions thereof.

It is the purpose of the herein described device to indicate the actual position of the drill stem in its relationship to a true perpendicular or vertical within approximately one-half degree of accuracy.

This is accomplished mainly by providing guides for the contact point II! in the form of the inverted V-shaped upper ribs 1 of the insulating rings I23 separating the contact rings H9 to I22 and surrounding the core I23. These elements, by reason of their downwardly inclined opposing faces, assist in directing the contact point II1 into engagement with one of the contact rings M9 to In on each side thereof, as well as the core I23. The assembly is illustrated in Figures 2 and 10 and diagrammatically shown in Figure 9.

To more clearly indicate the function of the upwardly projecting ribs Z of the insulator rings I 23, it may be stated that should the drill stem, inits downward course, actually assume an inclination from a vertical of the order of 2.75 degrees, the pendulum I00 will assume a true perpendicular position when drilling operations are ceased, that is, when the rotation of the drill stem has ceased rotation. Obviously, if the drill stem has deviated from a vertical, the bob I II secured to the lowermost end of the pendulum I00 will assume a position above the third of the insulatorrings I23 and suificiently past the rib Z thereof to cause the point III! to be deflected downwardly into contact with the third contact ring I 20.

When the apparatus is energized, therefore, the solenoid H0 in the bob III will operate to urge the contact point IIl downwardly to engage the contact ring above which it is suspended or cause the same to engage the rib l thereunder or one of its inclined faces and be directed downwardly thereby to contact the surface of one of the rings II9 to I 22 depending upon which side of the rib Z the contact I I1 first engages. The contact point I", to be better suited for the function just described, is provided with a relatively blunt rounded lower end to better enable its deflection by the inclined surfaces of the insulator rings I23.

It will be noted, that since the several contact disks 65, 66, 61, 68 and 69 must operate in sequence v til of theground segment H (32) and shown in Figure 9, serves as a ground connection, for the controlling circuit of the solenoid H34 Referring more in detail to the pendulum I03 it is pointed out that the latter is provided with an integral circular portion I25, as shown in Figure 2, and beneath which extends four integral guides or fins I21, which taper inwardly toward the bottom of the pendulum I llmand which extend laterally and radially from the metallic conduit 99' which is arranged longitudinally through the center of the pendulum I3I). This assembly with the exception of the metallic conduit 93' is made up of a tough, strong, non-conducting and nonmagnetic material. The bob III may be made of brass or the like, being substantially conical in form and is provided with a chafing ring I28 as is shown in Figure 2 of rubber or the like, to

afford a bumper or shock absorbing medium to prevent the bob 'I II from coming into sharp contact with the inner walls of the casing 3, should the pendulum I80 oscillate abnormally from shock or motion of the drill stem while in operation, or from handling the apparatus while out of the drill stem.

It is further pointed out that the pendulum assembly is so designed that the major portion of its inherent weight is concentrated within the bob I II at the bottom of the assembly. as is shown in Figure 2. Therefore, suspended as it is, by the universal ball bearing assembly 96, 91 and 98, as shown in Figure 2, the pendulum assembly has a strong tendency to maintain a true vertical position under all operating conditions, when the appliance. is properly positioned within the drill stem. Further attention is directed to the fact that as the applience is rotated by the drill stem 2 as in drilling, very little rotating torque can be actually transmitted through the universal ball bearing assembly 96, 91 and 98 as shown in Figure 2 from the casing 3 and the metal retaining collar I3I to the pendulum assembly.

Therefore, in relation to the rotating speed of the drill stem 2 and the casing 3 and the metal device consists of a series of dry cells I5 previously referred to, which are properly housed within the lower portion of the casing 3, as illustrated in Figures 3 and 4. It'will be noted, by reference to Figure 4, that the battery is made up of dry cells I5 connected in parallel series to provide a battery with a suflicient load potential and capacity for eflicient operation. The assembly of the cells I5 is such as to provide a simple, practical and positive energy source which can be conveniently replaced when necessary. As illustrated in Figure 4, several dry cells I5 are grouped and connected in series to provide each of the three parallel circuits of the battery. Each series of the dry.cells l5 illustrated in Figures 3 and 4, are inserted into a protective case I32 of durable insulating material. As, shown in Figure 3, each cell I5 is separated and cushioned by. the flat ring of rubber or other suitable material I3I.

two revolutions in a clockwise direction.

The 7 spring tensioned contact 529, illustrated in Figure 3, is positioned near the lower extremity of each of the three ii'isulatingv tubes I32 which surround and house each group ofthe five dry cells I5, and preferably is fixed thereto to provide a positive contact with the negative pole, or the outside case of the lowermost dry cell I5 of each group and to afford a ground connection to the casing 3. The coil spring contact I29 functions as a ground connection for the lowermost group of dry cells. As illustrated in Figure 4, the three positive connections for the three parallel circuits incorporated into the dry cell arrangement of the battery are so arranged as to make proper electrical connections with the positive post 933,

. through the latter to the main positive circuit I I6,

and thence through the latter to the switch lI, illustrated in Figures 2 and 9. 7

As illustrated in Figure 3, a contact is made between the dry cells I 5 and the post I33 through a flanged metal plate I33 which bears against the head portion iw' of the post I30 and which is retained in the annular recess n of an insulating collar I34 by an insulating ring I3I atop the-dry cell I5.

The contact post.I projects upwardly through 1 a central aperture in a circular plate I which is provided with a boss I35 projecting downwardly through an opening in a metal ring I36 which is welded to the walls of the casing 3 and provides a partition therein as well as an anchor for the assembly. A spring I31 affords a tensioned contact between the positive post of the uppermost dry cell I5 and the plate I33, aswell as affording a series connection between each dry cell I5 of each group.

The circular flanged member I33, as shown in Figure 3, is connected to the flexible conductor I33 which extends downwardly through the conduit I36 in the battery casing I32 to a similar flanged member I33 at the top of each series of dry cells, shownjat o and p in Figure 4.

In each case as shown in Figure 3, the circular flanged members I33 are retained in position in the assembly between a disk of insulating material I3l thereabove, of ample thickness, and a flat insulating ring I3I therebeneath. Electrical contact between the circular flanged member I33 and the positive pole of the top dry cell of each group is maintained by a spring I31. Thus it will be. seen that the cell group is provided with three positive parallel circuits which make proper electrical connection with the positive post I30, shown in Figure 3, when the battery assembly is in proper position in the lower end of the casing 3. It is further pointed out that when the battery assembly is properly placed within the cavity provided therefor at the lower end of the casing 3 and the cap I38, shown in Figure 3, is threaded into position, the battery assembly is compressed upwardly and the contacts are made more secure. The rings I3I and I3I are compressible and absorb shock and vibration.

In practice, therefore, the invention is assembled as aforesaid and positioned in close proximity to the drill bit in the lowermost portion of the drill stem 2, which in turn is lowered into the well for the usual drilling procedure.

' As drilling operations progress the operator may, when desirable and from time to time, and

without removing any part of the drill stem, cause the device to function by stopping the drilling operations and rotating the drill stem one or As shown in Figure 2, the first operation of bringing the drill stem to a state of rest, will cause the switch'assembly II to continue a clockwise rotation by reason of the momentum imparted thereto, until the upwardly projecting lug I3a engages the spring tensioned stop Iii], positioned atop the retainer plate 86, when it is brought to a cushioned stop.

Since very little rotating torque can be transmitted to the switch assembly II through the ball bearing assembly 19, so and 8| shown in Figure 12, when the drill stem is again rotated one or two revolutions clockwise the switch assembly II will remain stationary while the collar 85 carrying the retaining plate 85 rotates with the casing 3 until the stop MB is brought to a sharp contact'with the lug I39 and the sudden impact against the latter forces the mercury imprisoned within the spiral-like passage IT! from the pocket or cavity I5 from whence it travels downwardly and around therethrough into the chamber 16 where it provides a connection between the contact point 9d of the'stem as and the connection EII. As illustrated in ,Figures 2, 3, 4 and-9, the contact point of the stem 88 of the switch assembly II is connected electrically by the flexible wire connection II 6 to the positive post I30 on the battery assembly.

Therefore, when the contact point at and the connection SI of the switch assembly II are connected in this manner by the globule of mercury, as above described, the motor 311, shown in Fi ure 1, is energized through the integral connection 9| of the retainer plate 79 which is in contact with the bearing assembly It, 80 and BI and the latter being in contact with the metal ring 82 to which the flexible connection I01 is attached and which extends upwardly-through the passage 25, as shown in Figure 1, the current is transmitted to the positive terminal of the motor 35 which latter is grounded to the casing 3 to provide a negative return circuit to the battery assembly, as shown in the diagrammatic illustration in Figure 9.

The motor 30, when energized, will function to rotate the shaft 3I and the gear assembly in the gear box 36 transmitting rotation through the shafts 35 and 52 to the sleeve 60 bearing the metal contact disks G5 to 69, the receiving disk BI and the contact segment H5 (62) all of the latter being integral with the sleeve 60 except the ground segment M5 (62), as hereinbefore stated.

The function of the contact disks I55 to 69. shown in Figure 1, is directly connected with that of the pendulum Iilii, shown in Figure 2, through the medium of the contact rings IIS to I22 and the core I23. When the bob III of the pendulum I 00 is suspended in a vertical position within the casing 3, as shown in Figure 2, the same will be above and in close proximity to one of the circular contacts III] to I22, or the core I23, depending upon the inclination of the casing 3 and the drill stem 2.

By rotation of the motor 30 the contact segment I I5 (62) closes the circuit through the two lower spring tensioned arms 64,-thereby energizing the solenoid III], shown in Figure 2, operating the plunger H2 and transmitting positive 'battery potential therethrough. The electrical circuit is then completed through the boss 92, shown in Figure 2, the ball I05 contacting the concave face 93, through the plunger I04 and the spring I06 which latter is connected with the metallic conduit 99" extending downwardly through the center of the pendulum I00. The circuit is transmitted through the metallic conduit as to the positive side of the winding of the solenoid II t, and to the plunger H2 through the spring IE3.

The negative contact for the solenoid III! is provided in a flexible insulated wire connection I09 and extends upwardly through the metallic conduit 98' of the pendulum it to the retaining plate I 03, shown in Figure 2. The circuit thlll provided is completed through the ball bearing assembly 98, 97, and 96 to the metal ring 95 and the insulated wire connection II 6, through the latter to the spring tensioned contact 66 contacting the segment H5 (62) and through the latter to the opposite spring tensioned contact 54 and thence to the casing 3, in the manner illustrated in Figure 9. r r 7 When the solenoid III? in the bob III is energized, as above described, the plunger H2 will be urged downwardly causing the contact point III to engage one of the circular contacts I It to I23, depending upon the inclination of the casing 3 in the drill stem 2, and energize the same, completing the circuit through one of the contact disks 55 to 59 and one of the circuits ,1, g, h, i and 7 and the corresponding spring tensioned contacts 6 3. The circuit will thus be transmitted from the contact disks to 58 through the sleeve 60 to the receiving disk SI, and thence through the flexible wire connection 26 to the contact I0 of the solenoid 6 to operate the plunger 8 upwardly,

causing the detonator 9 to impart a series of sharp taps against the under surface a of the member 5 fixed in the dome 4 of the casing 3. Electrical energy is transmitted through the cylindrical casing 60 surrounding the shaft 52 but, as shown in Figure 9, the ground contact H8 (62) is insulated from the sleeve 613 at m.

The device will operate to produce the audible signal hereinbefore described at regular intervals so long as the motor 30 continues to function and its electrical circuit remains unbroken. The circuit of the latter will not be broken or opened, until the apparatus is rotated by the action of the drill stem 2 and a sufficient momentum is imparted to the switch assembly II to displace the mercury from the chamber I9 and cause the same to return through the spiral like passage TI to the cavity or pocket I5 in which it normally reposes, as shown in Figures 2 and 8.

Once the mercury is displaced from the chamber H3 in the switch assembly II the metallic contact is broken between contact point so and the connection 9| and between the positive connection of the battery and the various circuits of the assembly. The solenoid 6 is energized only as the contact fingers $3.0m any one of the disks 65 to 59 are energized and transmit such energy through the tensioned arms 5d, shown in Figure 1, through the receiving disk BI and the arms 64 to the contact III of the solenoid 6.

When assembled the device is placed within the lowermost section of the drill stem 2 and is cushioned upon a shock'absorber, illustrated in Figure 12, and which consists of a spider I II integrally fixed within the drill stem 2 and which is provided with a central body I42 having a square opening therethrough accommodating a square vertically arranged shaft I43 to whose uppermost end is integrally fixed another central body I44 having radial fingers- I45, A cup-like member IdS'is integrally attached to the uppermost side of the body I44 and is adapted to receive the integral lug I4I of the threaded plug I38 of the casing 3; A coil spring I48 surrounds the shaft I43 and 'the.weight of the entire assembly, including the apparatus herein described, bears upon the spring Hi8 whose lowermost end rests upon the body Hi2 supported by the spider Mi as. previously described. The shaft M3 is free to move vertically through the body M 2 and thus afford a shock absorbing or cushioning device for the assembly. A cap or collar M9 is secured to the lowermost end of the shaft I63 by a pin I50, or the like, to prevent the shaft M3 from becoming dislodged therefrom.

The device is lowered into the role within the drill stem 2 and submerged within the drilling fluid and its actual submerged weight tends to lessen with depth, and in proportion to the increased, density of the drilling fluid. As mentioned hereinbefore the apparatus is concentrically retained within the drill stem 2 by the radial lugs 70 which are integral with the casing 3, as

illustrated in Figures 1, 2 and 3, and sufiicient clearance exists between the lugs i and the inner walls of the drill stem 2 to permit free longitudinal movement of the device within the latter when necessary.

- Since the device is urged downwardly against the shock absorber assembly only by its own submerged weight, coupled with the frictional action of thedownward movement of the drilling fluid,

any momentary upward force from below which can not be transmitted in any series proportion to the apparatus. The lugs 10, as shown in Figures 1, 2 and 3 are integral with the casing 3 near the uppermost and the lowermost ends of the assembly. Any twisting or bending of the drill stem 2 is not transferred to the casing 3 at any point.

Inasmuch as the dome-like structure 4, shown in Figure 1, is subjected to destructive abrasive action from the solid matter suspended in the drilling fluid this member is enveloped in a protective coating of rubber, or the like, and in such a manner that, while the dome 4 is fully protected, the conical member 5 is exposed and extends into the drilling fluid.

The drilling fluid consists largely of water under all ordinary conditions in rotary drilling and i the water content of the drilling fluid is an excellent sound conducting medium. That portion of the drilling fluid which is made use of for conducting the primary sound wave to the earths surface, is the column of drilling fluid which is confined within the steel drill stem. Therefore,

when the impact of the member 9 shown in Figure 1, against the conical member .5, is transferred into sound waves and propagated into the column of fluid confined within the drill stem, the latter functions as a resonator to further strengthen each sound wave in its propagation in the column of drilling fluid to the earths surface. As hereinbefore mentioned, under abnormal conditions in drilling, such as the extreme depth of the device in the well, or other circumstances which necessitate circulation of heavy drilling fluids while drilling, or other conditions wherein the sound signal is partially dampened out and 4 rendered inaudible to the ear of the operator, a

simple battery microphone with headphone is attached to some convenient point on the drilling fluid circulating system to enable the operator to audibly pick up the propagated signal distinctly.

Simple detonations are made use of in signalling with the apparatus so that the signal is distinct and apart from the other,normal oscillating sou nds arising from circulation of the drilling fluid, the operation of the pumps, and the like.

Although the invention has been described with great particularity, it is obvious that certain changes and modiflcations may be resorted to from time to time by those skilled in the art and such changes and modifications may be considered within the spirit and intent of the invention, and may also be considered as coming rality of concentric spaced contact rings positioned in cooperable relation to the contactor on the said pendulum, a multiple code transmitter means, means under the control of said transmitter means forstriking the casing in conl'orm-' ance with a code, circuit means controlled by the engagement of the contactor witha contact ring for selecting the code transmitted by the'trans-' mitter means. I

2. A borehole inclination transmitter comprising a casing capable of insertion in a borehole, a pendulum within the casing and suspended for universal motion therein, an extensible contactor on the pendulum at the extremity thereof, a pluralityof concentric spaced contact rings positioned in cooperable relation to the extensible contactor on the said pendulum, a multiple code transmitter means, means under the control of said transmitter means for striking the casing in conformance with a code, means for extending the extensible contactor to engage any contact ring which is adjacent thereto, circuit means controlled by the engagement of the extensible contactor with a contact ring for selecting the code transmitted by the transmitter means.

3. A borehole'inclination transmitter comprising arotatable casing capable of rotation and insertion in a borehole, a pendulum within the casing and suspended for universal motion therein, an extensible contactor 'on the pendulum at the extremity thereof, a plurality of concentric spaced contact rings positioned in cooperable relation to the extensible contactor on the said pendulum, amultiple code transmittermeans, means under the control of said transmitter means for striking the casing in conformance with any code, rotation controlled means for extending the extensible contactor to engage any contact ring which is adjacent thereto upon the cessation of rotation, circuit means controlled by the engagement of the extensible contactor with a contact ring for 

